Effect of temperature on inflorescence development and sex expression of mono- and poly-embryonic mango (Mangifera indica L.) cultivars.
Sukhvibul N., Whiley A. W., Smith M. K., Hetherington S. E., Vithanage V.
Author Affiliation: School of Land and Food, University of Queensland, St Lucia 4072, Australia.
Journal of Horticultural Science and Biotechnology 74 : 64-68
Abstract : The effect of temperature on inflorescence development and sex expression in two mono-embryonic (Irwin and Sensation), and two poly-embryonic (Nam Dok Mai and Kensington) mango cultivars was studied. Trees were subjected to natural winter temperatures to induce flowering prior to transfer into controlled environment glasshouse rooms under day/night temperature regimes of 15/5, 20/10, 25/15 and 30/20°C for 20 weeks. Inflorescence development did not progress when trees were held at 15/5°C. Cooler temperatures (20/10°C) delayed the start of anthesis (42.4 days) compared with trees grown at 25/15°C (23 days) and 30/20°C (16.1 days). At 20/10°C, the delay in the start of anthesis was greatest for Sensation (55.5 days) and least for Nam Dok Mai (25.5 days) while at other temperatures there was little difference between cultivars. The distribution of hermaphrodite flowers within the inflorescence was independent of temperature with the highest percentage found in the apical half of the inflorescence. There was an inverse relationship between the length of the anthesis period and temperature, with anthesis occurring over 30 days at 20/10°C and reducing to fewer than 10 days at 30/20°C. Temperature also had an inverse effect on the total number of flowers per inflorescence with 619.6 ± 108.0 (mean for all cultivars) at 20/10°C decreasing to 431.3 ± 80.5 at 30/20°C.